package ACWing.WeeklyRace;
//4719. 商品种类

import java.util.HashMap;
import java.util.HashSet;
import java.util.Scanner;
import java.util.Set;

/**
 * @author :chenjie
 * @date :Created 2022/11/19 19:02
 */
public class ProductCategory {
    public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        int n=sc.nextInt();
        Set<HashMap<String,String >> set=new HashSet<>();
        for (int i = 0; i < n; i++) {
            String a=sc.next();
            String b=sc.next();
            HashMap hashMap=new HashMap();
            hashMap.put(a,b);
            set.add(hashMap);
        }
        System.out.println(set.size());


    }

}
